There is growing evidence that some form of information input dysfunction predates the onset of schizophrenia and is a consistent trait of schizophrenics in both the acute and remitted stages of the disorder. Yet, despite the increasing consensus that some input deficit is implicated in schizophrenia, progress on the specification of this deficit has been sluggish. Although the study of schizophrenia has more than its share of nuisance variables that hinder research (7,14,16), the slow progress of process-specification seems to stem mostly from the task-oriented strategy that developed because of the absence of adequate models of normal cognition to guide research. Recent advances in cognitive psychology have produced converging models of early visual processing that have provided experimental psychopathologists with numerous paradigms to study clearly specified stages of processing from multiple perspectives. Thus, a powerful process-oriented research strategy that has several methodological advantages (56) is now possible. Using well-established theoretical models for early visual information processing, one can assess schizophrenics' input dysfunction with several paradigms that quantify these theoretical constructs in specific terms and predict a priori particular patterns of performance for both adequate and inadequate processing at each stage. By measuring the same processes from different perspectives over a series of studies, one can provide construct validation for hypothesized deficits, and circumvent confounding psychometric artifacts (14,15) that make the discrimination of specific cognitive deficits problematic. Converging lines of evidence from several investigators (57,62,63,95,106,114) suggest that poor prognosis schizophrenics have a perceptual organization dysfunction in their initial, wholistic processing stage. This theory not only integrates results of several studies of schizophrenics that had seemed contradictory, it also provides an explanation of other cognitive deficiencies in these subjects (56). It is the major intent of the research we are proposing to test this theory rigorously and to provide evidence that will allow greater specification of the nature of this deficit. Moreover, since the data suggest that this deficit is characteristic of only a specific subgroup of schizophrenics, poor prognosis patients, the proposed research will attempt to isolate some important discriminators of this subgroup of schizophrenics.